Notification email not working

I’m trying to configure the notification email to be sent after a form submission. The email test message is working fine. The thank you message is also showing up, the register is in the database but the message isn’t sent. I’m using the smtp configuration data of the service provider which is inmotion hosting. Any idea of what could b wrong here?

Russell,
I am having the same exact issue and i have 1.5.8 When I view the GuiForms the attempts are in the queue it seems like. Showing Total 5 and Unread 5. Which are the many attempts i tried to submit the form.